re: Did you know that JavaScript has had labels since ES3?!? VIEW POST

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I actually knew about that, but really, it's more of a curiosity than anything. Like in "see this weird trick in JavaScript!" "What?! Weiiiird..." Turns out that foo: 42 is a label followed by a number and not a key/value pair.

In JavaScript, especially in modern development, labels are basically useless.

Or is there by any chance a very useful way to use them?

The only decent use case is to break out of multiple loops. But then again, it's a very limited case where for some reason you have to use loops instead of a functional approach.

The possibilities are endless!

Fortunately they're not! 😂

 

The only decent use case is to break out of multiple loops.

In PHP we have e.g. continue 2; (continue the parent loop), or break 3; (break the grandfather loop) for this purpose ;)

We have goto but there's basically no legitimate use for it. The docs page has a bit of an Easter egg agreeing with that :p php.net/manual/en/control-structur...

 

Uh. That's even worse. Now instead of a descriptive label, one has to count the nested loops to find out what the heck this statement affects.

I don't prefer it, just stating it's there ;-)

My favourite is Swift that has continue label or break label to refer to what to continue or break, but no accompanying goto which I think is an important safety decision.

developer.apple.com/library/conten...

gameLoop: while square != finalSquare {
    diceRoll += 1
    if diceRoll == 7 { diceRoll = 1 }
    switch square + diceRoll {
    case finalSquare:
        // diceRoll will move us to the final square, so the game is over
        break gameLoop
    case let newSquare where newSquare > finalSquare:
        // diceRoll will move us beyond the final square, so roll again
        continue gameLoop
    default:
        // this is a valid move, so find out its effect
        square += diceRoll
        square += board[square]
    }
}
print("Game over!")
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